The John Harrison Moonphase Sea Clock
The exquisite GE 7 Clock has a Rhodium finish on a glass base.
Our range of Sea Clocks are inspired by the great John
Harrison. In each clock we have embodied at least three of the basic principles
from Harrison's first Sea Clocks.
Perhaps his most well known invention is the unique
escapement, which gives the clock its popular name, 'The Grasshopper'.
The subtle and almost silent, 'lock and release' action of the
pallets permits them to work without oil (and consequently be free of the
effects of changes in viscosity) and at the same time make it so enduringly
fascinating to watch.
The INVAR pendulums are linked at the back, which allow the
clock to function 'out of level'. Their gentle action gives each clock that
restful quality which is so typical of an earlier more tranquil age.
The Astronomer Royal, Edmund Halley (c. 1656-1742) was a
proponent of the Lunar distance method for determining longitude. The
observations and calculations required for this method took many hours and were
prone to error. The hand painted Moonphase dial (each signed and numbered by the
artist) on the Moonphase model symbolises this alternative method.
The clocks are normally mounted on a base of selected figured
mahogany inlaid with brass into which the winding key and hand-setter are
housed. The base is French polished which is generally recognised as the finest
finish that can be applied to wood.
The engraved dials are hand silvered as they were in
Harrison's day. The unusual seconds hand deserves special study. It sweeps
through 240 degrees going from 0-60 seconds before vanishing, only to reappear
instantly at zero again.
All the parts on each clock are hand finished (even the ones
you cannot see!), almost all of the non-moving solid brass parts are protected
with a thin layer of gold or rhodium.
The 8 day movement is protected by a framed glass shade, which
incorporates a winding hole to avoid having to remove the glass each week.
Each clock is individually serial numbered and so confident
are we of our quality that each clock comes with a guarantee for the lifetime of
the original owner
H 45 cm x
W 32 cm x D 21 cm
E-mail us the item number
of any clock
for a prompt response
or call us at 918-622-5575